Case Study: 56-year-old Caucasian male police officer has had mild but progressive exertional dyspnea after walking two flights of stairs. This condition has persisted for the past month. Dyspnea became worse today, prompting emergency room evaluation.

Which of the following statements about symptom duration in the interstitial lung diseases is true:

a) An asymptomatic phase of illness is rare in most interstitial lung diseases
b) Rapid symptom onset is common in idiopathic pulmonary fibrosis
c) Rapid symptom onset is common in some interstitial lung diseases, such as acute interstitial pneumonia and
            sarcoidosis
d) Lung symptoms are usually the first symptoms of disease in the connective tissue diseases when they involve the lung
e) Excessive sputum production is common in the interstitial lung diseases